The Collaborative International Dictionary of English v.0.48:

Purtenance \Pur"te*nance\, n. [Abbrev. fr. appurtenance.]
   That which pertains or belongs to something; esp., the heard,
   liver, and lungs of an animal. [Obs.] " The purtenaunces of
   purgatory." --Piers Plowman.
   [1913 Webster]

         Roast [it] with fire, his head with his legs, and with
         the purtenance [Rev. Ver., inwards] thereof. --Ex. xii.
                                                  9.
   [1913 Webster] Purulence